Abstract
We describe a femtosecond pump-probe study of ultrafast hopping dynamics of electrons in the Mott insulator following Mott-gap excitation at temperatures of 5–300 K. Hopping-induced response of the lattice and electrons is probed by transient reflectivity at mid- and above-gap photon energies, respectively. These measurements show an instantaneous hop, subsequent picosecond lattice deformation, followed by acoustic phonon emission and microsecond relaxation. Temperature-dependent studies indicate that the slow relaxation results from Hubbard excitons formed by pairs.
- Received 29 November 2010
DOI:https://doi.org/10.1103/PhysRevLett.106.207402
© 2011 American Physical Society